The present invention generally relates to an apparatus for intercepting and removing debris and trash moved within a liquid stream. In particular, the present invention relates to a self-relieving screening apparatus for intercepting debris and trash flowing through a conduit, pipe, channel, tank or well, and automatically elevating the intercepted trash and debris to a receptacle or conveying system.
There exists in the art many examples of self-relieving screening apparatuses for liquids, particularly for waste streams. Such apparatuses typically include complex mechanical drive systems such as cable and pulley systems, chain and sprocket systems, rack and pinion systems, or manual systems of similar design. The complexity of these mechanical drive systems typically involve many moving parts subject to wear and tear, which can lead to high maintenance costs. Also, because self-relieving screening apparatuses are generally located in an unmanned environment, reliability is essential. Reliability is questionable in apparatuses that include drive parts located near or within the waste stream because they tend to malfunction by becoming contaminated, corroded or jammed.